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arXiv · 1909.09470

Document Rectification and Illumination Correction using a Patch-based CNN

Xiaoyu Li·Bo Zhang·Jing Liao·Pedro V. Sander
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Abstract

We propose a novel learning method to rectify document images with various distortion types from a single input image. As opposed to previous learning-based methods, our approach seeks to first learn the distortion flow on input image patches rather than the entire image. We then present a robust technique to stitch the patch results into the rectified document by processing in the gradient domain. Furthermore, we propose a second network to correct the uneven illumination, further improving the readability and OCR accuracy. Due to the less complex distortion present on the smaller image patches, our patch-based approach followed by stitching and illumination correction can significantly improve the overall accuracy in both the synthetic and real datasets.

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Xiaoyu Li, Bo Zhang, Jing Liao, Pedro V. Sander. 2019-09-20. Document Rectification and Illumination Correction using a Patch-based CNN. https://arxiv.org/abs/1909.09470

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